“Many primary care professionals manage injection or infusion therapies in patients with diabetes. Few published guidelines have been available to help such professionals and their patients manage these therapies. Herein, we present new, practical, and comprehensive recommendations for diabetes injections and infusions. These recommendations were informed by a large international survey of current practice and were written and vetted by 183 diabetes experts from 54 countries at the Forum for Injection Technique and Therapy: Expert Recommendations (FITTER) workshop held in Rome, Italy, in 2015.”

Average skin thickness is 2 to 2.5 mm, with 90% of people under 3.25 mm.

Use the shortest needles: 6 mm for syringes, 4 mm for pen injectors. The short needles help you avoid injections into muscle. Injection into muscle increases risk of hypoglycemia and wide blood glucose excursions.

Acceptable injection sites: abdomen, thighs, buttocks, upper arms (usually on the back of the arm).

If an arm site is chosen with a 6 mm needle, inject into a lifted skin fold (otherwise you might hit muscle).

When using the 6 mm needle, inject into a lifted skinfold if you are a child or normal-weight adult. Alternatively, insert the needle at a 45 degree angle.

The preferred site for regular insulin (soluble human insulin) is the abdomen, for faster absorption.

Use needles only once. (Admittedly, many get away with multiple uses without much trouble.)

Don’t inject into lipohypertrophy areas. Lipohypertrophy eventually is an issue in half of insulin users. It is a localized area of swelling or lumpiness at the site of prior injections. It’s often easier to feel than to see. Injection into these areas causes erratic absorption of insulin, with potential widely fluctuating and unpredictable blood sugar levels.

Rotate injection sites to avoid lipohypertrophy.

If using cloudy insulins (e.g., NPH and some pre-mixed insulins), gently roll and tip the vial or pen until the solution is milk white.